Species Finder Species Posted Mar 02, 2018 American Shad Appearance American shad have an elongated body with a broad triangular head and deeply forked tail fin. They are silvery in color with a brown-black back. During spawning season, the shad takes on a more bronze hue. Maximum Size The IGFA World Record for American Shad is 11 pounds 4 oz. (5.1 kg). On average they grow to a total length of 15 inches (38 cm), with males going up to 5.9 pounds (2.7 kg); females tend to be larger, typically hitting a ceiling at 7.9 pounds (3.6 kg). Growth Rate Shad grow at a fairly quick rate in the early years, but slow down considerably at four years old. Geographic Range American shad are anadromous. They are distributed along the Atlantic coast from Newfoundland to Florida and are most abundant from Connecticut to North Carolina. In the Mid-Atlantic region, the American shad ascend essentially all major rivers. On the Pacific coast, the shad was introduced into the Sacramento and Columbia Rivers in 1871, and the species is now established throughout the coastline of North America and into the Kamchatka Peninsula in Asia. Habitat Water temperature is the most important ecological factor for American Shad, as water that is too cold can be harmful, generally avoiding anything below 46°F (8°C). Shad tend to stick the bottom of the sea during the day, but swim closer to the surface through the night. Life Span Shad generally live anywhere between 5-7 years, though there have been incidents of shad reaching 11 years of age. Food Small crustaceans, fish, plankton and fish eggs. Reaches Reproductive Maturity Males mature around four years of age while females take a bit longer, hitting reproductive maturity at five in most cases. Reproduction Females can produce over 650,000 eggs, but many fail to hatch due to failed fertilization, predation, and other typical environmental hazards. The colder the water temperature, the longer it takes for the eggs to hatch. It takes as little as three days in warm water, to as long as nearly two weeks in cold. Spawning Spawning time varies depending on temperatures of the ocean as shad further south will spawn in mid-November while in colder waters it generally takes place in the early summer. Shad swim as far upstream as possible so that their eggs don't drift into saltwater until the fish are hatched. Migrations Shad are scattered across the Atlantic coast in winter months, but congregate in large schools in a few select locations in warmer seasons: Gulf of Maine, Chesapeake Bay and Bay of Fundy area being prime examples. They generally return to the same river as where they were born to spawn. Predators Seals pose the biggest threat in the marine world for American shad. Information Credit: U.S. Geological Survey.